I don’t think most modern Disney movies will become “Disney classics”, simply because they are mostly sequels. They aren’t bad, they just aren’t good enough / unique enough to become classics.
Most of the likely Disney classics from 2000-2010 will be Pixar movies: Monsters Inc, Finding Nemo, Incredibles, Cars, Wall-E, and Up, Princess and the Frog likely being the only Disney movie to reach that status.
2010-2016 saw a ton of potential classics from Disney with Tangled, Wreck it Ralph, Frozen, Zootopia, and Moana but only Brave and Inside Out from Pixar.
Since then it’s been mostly sequels from both studios. 2016-current I think only Coco becomes a classic from Pixar and only Encanto from Disney… maybe Soul and Raya will get there also with some more time.
I think many of the sequels (Frozen 2, Cars sequels, etc) will remain very popular but I don’t think that makes them classics. They will just be seen as a continuation of the original “classic” film.